The proposed R34 will develop and test a screening and brief intervention package for addressing substance use (SU) in pregnant and postpartum women in evidence-based home visiting (SBI-HV). Perinatal SU is an urgent public health concern, with significant negative impacts on maternal and child health. Pregnant and postpartum women who use substances are at high risk for losing their children to the child welfare system. Many perinatal women conceal their SU and do not actively seek treatment, increasing risk to themselves and their children. As the primary supportive intervention offered to high-risk families during the perinatal period, HV is a promising venue for addressing SU in this population. However, there is currently no systematic protocol for addressing SU in routine HV, leaving many HV clients with unmet needs that increase maternal and child risk. SBIRT is widely endorsed in primary care to improve SU identification and decrease use among low-to-moderate users, and has potential applicability in HV. Two challenges to implementing traditional SBIRT in HV are: (1) clients are reluctant to disclose SU due to fear of child removal; and (2) home visitors lack the training and clinical skill to deliver evidence-based brief interventions with fidelity. The proposed SBI-HV represents an innovative adaptation of the SBIRT framework, designed to leverage technology and two key elements of the HV context (the home visitor-client relationship and routine supervision) to overcome these challenges. The SBI-HV will include (a) a two-session computerized screening and brief intervention (e-SBI), adapted from a validated e-SBI developed by the Co-I that has proven effective in reducing SU in pregnant and postpartum women in primary care; and (b) implementation supports for enhancing routine HV service delivery and supervision to promote effective e-SBI integration in the unique HV context. The SBI-HV will be designed so that clients are never required to disclose SU to home visitors. The e-SBI is fully automated and self- administered; home visitors will not see clients? responses, and will not be asked to implement evidence-based interventions. Specific aims are to (1) develop the SB-HV (e-SBI intervention plus implementation supports); (2) evaluate its feasibility, acceptability, and fidelity; and (3) determine its preliminary impacts on symptom reduction (SU, depression, parenting stress), HV retention, and SU treatment engagement. We will partner with 2 pilot sites to construct the SBI-HV guided by stakeholder input (Aim 1). We will then conduct a small RCT in 2 additional sites. Home visitors (N = 10) will be randomized to HV+SBI-HV vs. routine HV. Feasibility, acceptability, and fidelity will be assessed via HV and client interviews and fidelity checklists (Aim 2). Research assistants will interview clients (N = 40) at baseline, and 3- and 6-month follow-up to track SBI-HV impacts (Aim 3). If results are promising, the next step is an R01 to test the SBI-HV in a larger trial, spanning multiple states and HV models. If effective, the SBI-HV would fill a significant gap in HV services and has potential for widespread deployment in state HV systems.